Imaging detectors for photons in the 10 to 150 keV energy range have many uses in medical technology including tumor imaging, SPECT, and radiography. Digital output is particularly useful since it allows image enhancement, analysis, transmission and storage. An approach is proposed for developing a new technology, using CdZnTe detector material, which would allow images to be obtained with 100 u spatial resolution and energy resolution of 2% or better. This capability would facilitate entirely new classes of medical diagnostic procedures. For example, "dual energy" angiography could now be done using a polychromatic x-ray source. The present effort will demonstrate the feasibility of the conceptual approach and create the technological foundation upon which later, application specific instruments can be built. Detectors will be modeled, using Monte Carlo and electron transport, to predict their signal outputs. These outputs will be compared to measured signals to validate the models. The models will then be employed to develop signal processing algorithms which achieve the desired energy and spatial resolutions. Finally, electronics will be designed to implement the algorithms. In Phase II a working model would be constructed and tested. PROPOSED COMMERCIAL APPLICATION As an energy resolved digital detector with 100 u spatial resolution, the proposed detector technology could find many medical applications, including SPECT, energy resolved angiography for small mammals, bone densitometry on rodent bones, and small, hand-held gamma cameras. Non- medical applications would include non-destructive testing, astrophysical gamma imaging, nuclear cleanup uses, and scientific instruments.